Russian President Vladimir Putin’s repeated nuclear threats against member-states of the North Atlantic Treaty Organization (NATO) for interfering in Russia’s invasion, occupation, and annexation of Ukraine are escalating as the war goes badly for Moscow. His threats are not going unnoticed as the American public shows significant concern amid a renewed interest in the role of nuclear weapons in national security.
For many Americans, any discussion of nuclear weapons use generates images of large-scale exchanges of intercontinental ballistic missiles (ICBM), submarine-launched ballistic missiles (SLBM), and strategic bomber–delivered nuclear cruise missiles. This is, broadly speaking, an image of the United States and Russia engaging in, what the military calls, a full-scale nuclear exchange. Fortunately, this image of nuclear Armageddon is far less likely than a limited use of nuclear weapons on the battlefield in Ukraine. Unfortunately, Russia possesses an estimated 3,000–6,000 low-yield non-strategic nuclear weapons designed for use in just this type of conflict.
Before we go any further, let us specify that the term ‘yield’ is used to compare a nuclear weapon’s energy output by equating it to an equivalent explosive energy of TNT, where a kiloton (kt) is a thousand tons. It is also worth noting that there is no universally accepted yield range for categorizing nuclear weapons. We suggest that a low-yield weapon produces between one and ten kilotons.
For comparison, the nuclear bomb dropped on Hiroshima was about fifteen kilotons. By contrast, the Minuteman III ICBM delivers a nuclear weapon with an estimated yield of 300–475 kilotons. Thus, suggestions that all nuclear weapons are somehow the same belies a lack of understanding of just how powerful some nuclear weapons are, and others are not.
When the 2018 Nuclear Posture Review called for low-yield options like the W76-2 warhead for the Trident D-5 submarine-launched ballistic missile, which has an estimated yield of ten kilotons, it was in an effort to balance against Russian low-yield weapons. It is primarily low-yield weapons that are of most concern for use in Ukraine, not strategic weapons. These weapons produce yields far larger than the GBU-43 Massive Ordnance Air Blast (MOAB) – eleven tons – the largest conventional munition in the American arsenal. Nuclear weapons have a major advantage in their size and weight, and thus are more easily delivered than the GBU-43 to a militarily-relevant target.